WAFER SINGULATION PROCESS CONTROL

Technical Field

The present invention generally relates to electronic and integrated circuit device manufacturing.

Background Art

Electronic equipment and in particular integrated circuit device to the making of a large number of manner, wherein a plurality of such a device on a single substrate are formed simultaneously. Various size, shape and the base of the composition is common. Form the substrate examples of materials can include but are not limited to silicon, sapphire, gallium arsenide, glass, plastic, epoxy resin, and by any any of the foregoing substances or analogs of various composition, composite structure or compound semiconductor.

Upon completion of the manufacture of the equipment on the substrate, these devices must be separated from the base. The electronic or IC device are separated from each other called cutting. This is usually a substrate adhered to the support body or the support member realized, such that when the device when separated from each other, the position of the still is known. The support body may comprise a film or with frame and with the to be separated into a plurality of single device substrate the same or different types of auxiliary substrate. By technical personnel in the field known many method, including but not limited to cutting and marking, to complete the separation. In the sawing operation, thin diamond saw between devices to pass through the substrate and are separated from each other. The saw is used for cutting the substrate, rather than install base of the support body. Similarly, the marking operation can be used in mechanical or laser scribing tool to be separated on the base of the apparatus between the generating line. However, in the operation of the marking, the marking of the substrate along the scribe line disconnect in order to separate the individual devices. In these two kinds of operating in, now separated apparatus maintains the adhered on the support body, so that it can be used for the subsequent manufacture or packaging operation.

In order to properly control the cutting operation, according to the arrangement of the need in the past and arranged for characterizing the present results. Then, the characterization can be used to modify ongoing process, in order to predict suitable for cutting process and/or the arrangement of the identification of the ongoing of the cutting course minus emergency feature. Characterization cutting operation a usual mode relates to machine vision application of the technology. However, these methods generally require the application of complex Image processing technique to extracting the cutting operation the characterization of useful information. Therefore, the need for a single device and from the base Image in information simple technology.

Content of the invention

Of the present invention in one embodiment, based on the captured by the inspection system of a single IC device features found in the Image to assessment monitoring and at least partially control the cutting process. In the images, can identify the peripheral edge of the device, and these edge fragments can and adjacent equipment compared to the edge of the fragment, to identify these edge fragment difference part. Differences of interest can include but is not limited to roughness, chip, layered and misalignment. The same technology can be used to determine the separation of the edge of the IC device of the proper positioning of the IC device and with the center portion of the edge alignment. Can be revised accordingly such as feed rate, temperature, pressure and aiming at the cutting process variable.

Description of drawings

Figure 1 is the schematic view of the substrate used for capturing the Image of the universal vision system.

Figure 2 has shown the and formed with a plurality of equipment of a part of the substrate, these devices are fixed to the supporting body and have been separated from each other.

Figure 3 is a single device common geometric shape, including difference part.

Figure 4 A and 4 B is to identify a single device and the difference between the portion of the schematic view of a method.

Figure 5 is the flow chart of according to the invention of a method.

Figure 6A - 6C can be quantized to the auxiliary control of the cutting process of the characteristic of the schematic view of the edge of the apparatus.

Figure 7 is the schematic view of the apparatus with respect to its edge.

Mode of execution

In the invention the following detailed description, forming a part thereof with photos to reference, and through the graphic mode has shown the can implement the specific embodiment of this invention. In the attached drawing, in the several views, similar digital description of the part similar to that of the. In sufficient detail to describe these embodiments, so that the technical personnel in the field to implement the invention. In the without departing from the scope of the invention circumstances, may make use of other embodiment and structural, logical and electrical changes. Therefore, the following detailed description should not be considered as a limitation, and the scope of the invention only by the attached claims and their equivalent to limit the description.

Figure 1 are shown for capture substrate 20 Image universal machine vision system 50. System 50 comprises illuminating light source 52, and in this case to the arrangement of the bright field lighting solutions; and the imager 54, the most commonly used is the digital camera, includes a vision system 50 of the imaging plane of a charge coupled device (CCD) or complementary metal oxide semiconductor (CMOS) type Image sensor. Beam splitter 56 will light source 52 is coupled to the system 50 in the vertical path, so that the light from the light source 52 is incident substrate 20 on, then from the substrate 20 to return to the imager 54, it will from the base 20 and the return light to form the Image. The technicians of this field already know type of optical element (not shown) with the light source 52 and the imager 54 associated, in order to ensure that from the source 52 of lighting, the object (substrate 20) and imager 54 of sensor mutual conjugated in order to produce the appropriate focusing and exposure of the Image. The optical element may include a lens, the objective lens, filter (wavelength and intensity), a polarization filter, a spatial filter, light beam shaper, reflector (active or passive) and the like.

Technical personnel in the field will understand that, although shown and described the vertical incident system 50, but may also take into account additional or alternative imaging system. For example, can provide alternative or optional lighting light source (not shown) to direct light to the substrate 20 on, in order to facilitate the dark field imaging scheme commonly referred to as. Can provide any suitable number of bright field or dark field illumination light source 52. The imager 54 can be provided with more than one Image sensor in order to utilize the advantages of various lighting solutions. Further, the light source 52 can be relative to the base 20 to one or more incidence angle and/or azimuth angle arrangement.

According to the light source 52 and the imager 54 of sensor arrangement, the obtained Image can be coded to control the cutting process of the interest in the substrate 20 of the various features. By the imager 54 output Image is usually based on pixel, pixel value by an array, when the present Image, faithful interested substrate 20 of the characteristic. Pixel of the digital Image is mapped to the substrate 20 corresponding to the position of, and each pixel value expressed by reflection, refraction, scattering or emission from the substrate 20 to return to the position of the light. The pixel value typically is involved by the imager 54 on the basis of the sensing of the light intensity, but also can relate to the substrate in various wavelength, polarization state, incident angle and/or the azimuth or the scattering strength characteristic correlation data.

From the system 50 is provided to the Image analysis of the Image obtained controller (not shown). The controller may be in the local or remote operation mode of operation any useful configuration local or networked computer or processor.

Figure 1 shown in the substrate 20 is expressed as the supporting body 26 on the silicon of the 22, in this case is a ring of the film frame, it has membrane or with the center hole of the cover, the wafer 22 is adhered to the film or tape. The base 20 relative to the system 50 mobile (arrow 28), in order to allow its integrity or single state caught under the substrate 20 all or part of the Image. The movement of the base plate there are technical personnel in the known types of platform or table (not shown) to provide. Although the arrow 28 said linear movement, but may also take into account the curvilinear motion, such as by the substrate 20 due to the rotation of the movement of the curve. Normally through the base along the through the imager 54 boustrophedon path or spiral path of movement of the scanning of the whole base. Can also be segments or sample imaging.

Figure 2 shows that have been singulated substrate 20 a part of. Each IC device 30 substantially sequentially positioned in a rectangular array, although it is possible for this kind of apparatus 30 are arranged in different geometric pattern. Usually, apparatus 30 is characterized in that the central area 32, it includes some circuit or other structure, such as micro-electro-mechanical structure (MEMS). Each of the devices having an outer peripheral edge 34, its around the central area 32, at intervals of a predetermined amount and, to ensure that the center region 32 of the circuit or structure will not damage the cutting process. As mentioned above, through the device 30 between the rows and the operation of the saw blade or scribe (laser or mechanical) to realize the cutting. Apparatus 30 of the rectangular array usually looks like the city map, wherein the with the apparatus 30 corresponding to the block and between the equipment looks like of urban streets interval, due to the fact that, therefore this interval is usually known as the "street". For the sake of brevity, the invention will only be described by saw cutting, but it should be understood by other method of cutting is very similar and is included in the in this specification.

In the device 30 between the rows of the "street" 36 in, saw blade (not shown) in the device 30 through. Street 36 is considered waste area, because they will be destroyed in during cutting. In the process for producing a device substrate 20 period, can be in the streets 36 formed in the various process control and test structure, but they usually is the destruction of the cutting process. In fig. 3 in, more clearly see the street 36 and defining the peripheral edge 34. In the Figure, can also identify a single device 30 of the peripheral edge 34 of a single edge segment 38. A plurality of passage 38 common forming apparatus 30 of the peripheral edge 34. The passage 38 can be a peripheral edge 34 of any arbitrary part, its from the adjacent device 30 of the corresponding fragment 38 together, define or describe the streets 36 in the sawing. In one embodiment, the edge fragment 38 along the straight line of the equipment on behalf of the 30 the entire lateral surface, that is rectangular or square equipment 30 extending from one side of.

In fig. 3 in, passage 38 shown is essentially are generally linear. In most cases, the cut is made linear process the segments 38 also nominally is linear. However, for many reasons, the streets 36 in the saw cut may be from a straight line path, correspondingly, edge 34 of the passage 38 to the exaggerated curve way shown.

Figure 4 A and 4 B shows a cutting process that may occur in the two types of the difference. In fig. 4 in, adjacent passage 38' and 38" are overlapping, in order to amplify the visual on each segment any difference. As can be seen, the passage 38' has deviated from the fragment 38" of the edge part. The passage 38' and 38" not along its length on any point of the intersection. In the fragment 38 is covered and there is no fragment formed by the intersecting gap 40 of the cases, it can be assumed that a gap is formed wherein the 40 of the passage 38' portion has a chip or omit some material.

In fig. 4 B in, passage 38' and 38" once again overlap, in order to amplify the visual on any difference between them. In this example, segment 38" towards the passage 38 'extends and passes through the passage 38' of the gap 42. In the such as the fragment 38 "of the fragment has towards its corresponding fragment 38' extending and intersecting gap 42 of the cases, it can be assumed that the edge 38" with a part of the so-called hierarchical. In this case, the edge fragment 38" have lost a portion of some of the material or in the form of cracks which already has, make the apparatus 30 in its periphery at the edge of the defect, the defect will not completely through from the top to the bottom of the base 20 extend.

It can be expected, each of the devices 30 and its peripheral edge 34 and an external is the presence of by the system 50 of the Image is determined. Connected to the system 50 of the controller analyzes the captured Image and identifying each of the devices 30 of the peripheral edge 34 of the position. Depends on the resolution, the imaging system 50 and its numerical aperture, by the imager 54 capture field of view can include a plurality of device 30, a single device 30 or one or more of device 30 of a part. Because the present invention relates to apparatus 30 of the peripheral edge 34 of the adjacent segment 38 assessment, therefore does not include how to analyze the picture in order to allow analysis of the detailed review. It can be said that, technical personnel in the field to a plurality of well-known is the region of interest in a sample Image in order to obtain comparable segment 38 of the Image. Similarly, the field is known from the discrete selected in the Image comparison part to, or connected to a plurality of Image in order to obtain with possibly from its derived with regard to equipment 30 or fragment 38 more visual information of the Image.

In one embodiment, fragment 38' and 38" by the system 50 imaging. The passage 38 'and 38 "can be similar to the United States Patent no 5696835 entitled" Apparatus and method for aligning and measuring misregistration "technology, in order to capture the Image recognizing fragment 38' and 38". The reference literature by reference into this text as a whole. Each fragment can be determined best-fit line, then used to "cover" the passage 38' and 38". In one embodiment, this can be by generating the passage 38' and 38" of the position and orientation of the associated with each other to complete the transformation. In another embodiment, the passage 38' and 38 "overlap each other to generate a composite Image (as herein used, the term" Image " can represent the actual digital Image and the pixel information of the array). In all cases, keep the fragment 38' and 38" with the orientation of the cutting process in order to keep the quality of the information.

"Covering" fragment is not a must be directly done. Simply know that fragments of the position of the pixel, or discern the best formula to be line, or that have been identified on the basis of the Image primitive data should allow people to carry out subsequent identification step. "Covering" simply refers to the profile of the known relationship is formed between the steps, it allows subsequent differences in the occurrence of the identification step. This may be a simple conversion to or from two separate Image forming a new Image or Image primitives direct relationship.

Once created conversion or synthetic Image, can be measured fragment 38' and 38" the distance between the. This can be accomplished by segmenting, wherein each vertical position of the lateral distance between the measuring segment. Figure 6 A has shown the fragment 38' and 38" in the name of perfect on the arrangement. In the Figure, the passage is parallel to the straighter, this is the ideal arrangement of the fragment. Figure 6 A can be expressed substrate 20 or fragment 38' and 38" of the actual peripheral edge 34. The passage 38' and 38" is the distance between the of interest, because it can be used for cutting the substrate 20 is directly related to the width of the saw. The distance of the supporting body may also relate to the tension of the film. The supporting body is not appropriate in the film may cause the tension of the cutting device 30 is pulled apart away from or towards each other, such that a single device 30 the distance between the is too small, too large or non-uniform, as shown in Figure 6 B shown.

Figure 6 C illustrative has shown the form and include the fragment 38' and 38" of the composite or the superimposed picture of the embodiment. In the Figure, the passage 38' by straight dashed line represents, the segments 38" expressed by the curve of the line. Figure 6 C can also indicate had been targeted by the curve segment 38" for the calculation of the best-fit line (dotted line).

First of all consider Figure 6 C as shown in the synthetic Image representation, it can be seen that the upper part of the composite Image, the passage 38' and 38" substantially collinear. Note, by using the straight line to indicate that the fragment 38', highlight the change between the two segments; the passage 38 is generally not perfectly straight, and more generally to a certain extent is curvilinear, in particular at very small scale. The passage 38' and 38" of the lower part of the significant change, this indicates that a problem exists with the cutting process. In a selected vertical position measuring fragment 38' and 38" of the horizontal distance between the transverse/highlighted in generating these edges 34 of the problems inherent in the cutting process. In the upper part of the passage, the distance between the fragments is relatively small, and preferably, is relatively close to zero. In the fragment 38' and 38" of the lower part, the greater the distance change and can be very large. In fact, we can clearly see the gap 40 and 42. If the relative to the arbitrarily selected by the fragment 38 measurement, can easily determine the clearance 40, 42 may be chip whether or layered.

Also can be selected by determining the vertical position (note, these position can in each pixel line place or in the selected position of the smaller subset) of the lateral distance between these lines, or the use of these value or its absolute value to determine the edge 34 or relative to each other with respect to the optimal to the variability of the line, to calculate the fragment 38' and 38" between the best-fit line or (dashed-line) and fragments (solid-line) between the standard deviation. Under the selected resolution or the proportion of the high variability can provide a good indication of the quality of the cutting process. In fact, exceeds the standard deviation is set as the measurement distance or of a certain level of the cut quality of a threshold can be used to determine the deviation of the nominal outline whether there was any inconsistency.

Figure 7 shows the another aspect of the invention. Device 30 has a central region 32, wherein there can be various types of active circuit or MEMS structure. Preferably, the apparatus 30 of the peripheral edge 34 will be parallel, and preferably with the central zone 34 of the peripheral edge of the 35 spaced out uniformly. With the above on the assessment of the passage 38 in the manner described in substantially the same way, can identify the central area of the peripheral edge 35 of the passage, and with the apparatus 30 of the peripheral edge of the passage 38 of growth. Because the central area 32 is usually formed using lithographic techniques, so that its peripheral edge 35 are often quite is linear. In any case, the center region 32 of the peripheral edge 35 having a known shape of the nominal shape. In the device 34 and the edge of the central area 35 measuring distance between Δ X, Δ Y and θ, and it can be instructed to in the course of cutting whether there is misalignment. Further, in the substrate 20 on the device 30 of the array of Δ X, the value of Δ Y and θ changes, can be a pointing device 30 of its own not aligned or in the implementation of the apparatus at the time of cutting in the progressive alignment error. These error may be at an earlier time indicating the problem, such as not appropriate to form a composite substrate (reconstruction of the wafer, for example embedded in the epoxy resin or mounted to the carrier on the substrate of the chip, or may be, the substrate 20 on which the crystal structure of the form of the apparatus 30 is not aligned.

Figure 5 shows the implementation of the process of the present invention of one embodiment. In step 80 in, system 50 for capturing the support body or on the base of the apparatus 30 of the Image. In step 82 in, is coupled to system 50 of the processor analyzes the captured Image in order to discern the edge 34, and when necessary, discern the edge 35. As mentioned above, can be of the edge 34 and 35 of the passage used for comparison. In step 84 in, covering or comparing the extracted edge 34 and/or 35 of the passage, in order to discern the difference and quantify the quality of the cutting process. Then-use maps 5 as shown in the output of the process to improve the cutting process, by this apparatus 30 from the substrate 20 is separated and potentially identifying the substrate 30, and the cutting process on the basis of their edge is obtained by the difference of the practicability of with suspicious or quality.

In one embodiment, can be expressed chip or layered gap 40, 42 of the existence of the problem can be instructed to the cutting process. In the passage 38 in a great variation of the same or the standard deviation can be instructed to this kind of problem. The peripheral edge 34 and 35 between the distance or angle of the change of the orientation can indicate the misalignment in the cutting process. These data can be fed back to the cutting process in order to improve the alignment, feed rate, tool maintenance, film application techniques.

Conclusions

Although the invention has been illustrated and described a specific embodiment of the present invention, but the field to technical personnel will understand, are calculated to achieve the same purpose of any arrangement can be substituted for the specific embodiment shown. For the ordinary technical personnel in the field, many of the improvements of the present invention is obvious. Therefore, the application of the present invention is intended to cover any adaptations or changes. It is obvious, this invention only by the attached claims and their equivalent restrictions described.